Conventionally, a casing of an electric junction box mounted on a car body accommodates a laminate composed of bus bars formed by punching a conductive metal plate into a predetermined configuration and insulating plates layered on the bus bars alternately and circuit components consisting of an insulating substrate on which an electric conductor of a copper foil or the like is printed in a required pattern to form a printed-circuit board. When one casing accommodates a plurality of circuit components layered one upon another, electric conductors of the circuit components are connected with one another through a relay connector.
An electric junction box 1 of this kind accommodating the relay connector is provided, as disclosed in Japanese Patent Application Laid-Open No. 2001-15952 (patent document 1). As shown in FIG. 9, the electric junction box 1 has the laminate 2 of bus bars and the printed-circuit board 3. The housing (relay connector) 4 accommodating the relay terminal (not shown) is projected from the insulating plate of the bus bar laminate 2. The bus bars of the bus bar laminate 2 are connected with the relay terminal from below, and one end 5a of the connection terminal 5 is connected with the relay terminal from above. The other end 5b of the connection terminal 5 is soldered to the electric conductor of the printed-circuit board 3. Thereby the bus bars of the bus bar laminate 2 and the electric conductor of the printed-circuit board 3 are connected with each other.
But the number of circuits has increased owing to a rapid increase of electric and electronic parts in recent years. Thus in forming a required circuit from two circuit components, the circuit is necessarily horizontally large. The relay connector connecting the circuit components with each other is also necessarily large. Thereby the electric junction box is horizontally large.
In a construction in which three circuit components 6, 7, and 8 are accommodated in the casing of the electric junction box, with the circuit components 6, 7, and 8 vertically spaced at certain intervals, and the circuit components 6, 7, and 8 are connected with one another, it is possible to make the circuit components compact. But as shown in FIG. 10, it is necessary to form a housing 4 on the circuit component 7 located at an intermediate position and the circuit component 8 located at a lower position. Thus when the housing is formed on the circuit components 7 and 8, the interval between the circuit components is necessarily large. Therefore the electric junction box is very large in a vertical direction.
Patent document 1: Japanese Patent Application Laid-Open No.2001-15952